1.2.0 - Conversion to NetworkX's MultiDiGraph

• Added: prov.graph.prov_to_graph() to convert a ProvDocument to a MultiDiGraph
• Added: PROV-N serializer
• Fixed: None values for empty formal attributes in PROV-N output (issue #60)
• Fixed: PROV-N representation for xsd:dateTime (issue #58)
• Fixed: Unintended merging of Identifier and QualifiedName values
• Fixed: Cloning the records when creating a new document from them
• Fixed: incorrect SoftwareAgent records in XML serialization

1.1.0 - PROV-XML support added

• Added: Support for PROV-XML serialization and deserialization
• A ProvRecord instance can now be used as the value of an attributes
• Added: convenient assertions methods for ProvEntity, ProvActivity, and ProvAgent
• Added: ProvDocument.update() and ProvBundle.update()
• Fixed: Handling default namespaces of bundles when flattened

1.0.1: Bug fixes and minor improvements

• Added: Default namespace inheritance for bundles
• Fixed: NamespaceManager.valid_qualified_name did not support
  prov.model.XSDQName
• Added: Convenience prov.read method with a lazy format detection
• Added: Convenience plot method on the ProvBundle class (requiring
  matplotlib).
• Changed: The previous add_record() method renamed to new_record()
• Added: The new add_record() function which takes one argument, a
  ProvRecord, has been added
• Fixed: Document flattening
• Added: hash function added to ProvRecord (at risk: to be removed
  as ProvRecord is expected to be mutable)
• Added: extra_attributes added to mirror existing formal_attributes

1.0.0 - Rewritten data model

• The underlying data model has been rewritten and is incompatible with pre-1.0 versions.
• References to PROV elements (i.e. entities, activities, agents) in relation records are now QualifiedName instances.
• A document or bundle can have multiple records with the same identifier.
• PROV-JSON serializer and deserializer are now separated from the data model.
• Many tests added, including round-trip PROV-JSON encoding/decoding.
• For changes pre-1.0, see CHANGES.txt.